Palladium(II) acetate catalyzed stereoselective C-glycosidation of peracetylated glycals with arylboronic acids.

[reaction: see text] Addition of a variety of arylboronic acids to peracetylated glycals takes place in the presence of a catalytic amount of Pd(OAc)(2). The reaction involves the syn addition of a sigma-aryl-Pd complex to the glycal double bond followed by anti elimination of Pd(OAc)(2) to provide a carbon-Ferrier type product. This method provides a practical and convenient stereoselective synthesis of C-arylglycosides.